This is a great fictional book about an important historical event. So while you are getting entertained, you can actually learn some history too. Only drawback might be that it is a bit of a downer.

In 480 B.C. three hundred of Sparta's finest warriors (with some help) held back the invading millions of the Persian empire and valiantly gave their lives in the selfless service of democracy and freedom. You can visit the site today and see a memorial that roughly translates to "Go tell the Spartans, stranger passing by, that here, obedient to their laws, we lie."